By default, applications are being restricted by the operating system to limit the actions that might cause an issue to your machine. This usually causes the Operation not permitted error.
If you really know what you’re doing and you want to make modifications to your system files, like creating a symlink to another location, then you might have to give administrative priviliges to your apps (ie Terminal).
In my screenshot above, I’m trying to transfer the location of my iOS back-up to an external drive, but my 3rd party terminal app is being restricted which prevents me from doing it.
Step 1: Go to System Preferences and click Security & Privacy options.
Step 2: Go to Privacy tab, click the plus (+) sign and locate the app that you want to grant Administrative Privileges.
Step 3: Restart the app.
SUCCESS!!! Your application now have administrative privileges.
TIP: Be careful very very careful, I do not recommend deleting/modifying your system files unless you really know what your doing. Alwaus make sure to have a backup.